解方程组2x+5y=25,4x+3y=15
人气：129 ℃ 时间：2019-12-01 09:12:59
解答
2x+5y=25 (1)
4x+3y=15 (2)
(1)*2-(2)
4x+10y-4x-3y=50-15
7y=35
y=5
x=(25-5y)/2=0
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